Gemstone



FIG. 1 is a top perspective view of a gemstone showing my new design;

FIG. 2 is a bottom perspective view;

FIG. 3 is a top plan view;

FIG. 4 is a front elevational view;

FIG. 5 is a side elevational view; and,

FIG. 6 is a bottom plan view. 

The ornamental design for a gemstone, as shown and described. 